Hi,
> providing a mode in which the server would reject PQexec strings containing more than one query.
That wouldn't help a lot. The simple SQL injection is not detected:
ResultSet rs = stat.executeQuery( "SELECT * FROM USERS WHERE PASSWORD='" + password + "'");
An attacker would only need to use the following password:
' OR 1=1
The the SQL statements is still only one query:
SELECT * FROM USERS WHERE PASSWORD='' OR 1=1
Regards,
Thomas